ABB A43, User Manual, Page: 46 / 295

Technical Description
A43/A44 46
2CMC48001M0201
User Manual Revision: C
5.1 Energy Values
General
The energy values are stored in energy registers. The different energy registers
can be divided into:
• Registers containing active, reactive or apparent energy
• Registers containing different tariffs or total sum of all tariffs
• Registers containing energy per phase or total sum of all phases
• Resettable registers (possible to set to zero via buttons or communication
command)
• Registers containing momentary or historical value
The energy values can be read via communication or directly in the display with
the help of the buttons.
Primary value
In transformer connected meters with external current transformers, and some-
times also external voltage transformers, the total transformer ratio is taken into
account for all energy registers, that is all energy registers store primary values.
Presentation of register values
In direct connected meters the energy is usually displayed with 7 digits in kWh/
kvarh/KVAh with two decimals and displays one decimal less at overflow, that is it
changes to one decimal at 100000.0 kWh and to no decimals at 1000000 kWh.
In transformer connected meters where primary values are displayed, the
energy values can be rather big when the total transformer ratio is big.
Normally the meter automatically adapts the unit and number of decimals
displayed to the value.
In case the energy is displayed with fixed units and number of decimals the
energy will "roll over" to zeros when the energy is incremented if all nines are
displayed. The meter can however contain more digits internally, which can be
read out via communication if the meter is equipped with a communication
interface. See the example below where the value 2483756 is displayed, while
the internal register contains 192483756.6.